PT-141 (Bremelanotide)

PT-141, also known as Bremelanotide, is a 7-amino acid cyclic melanocortin agonist with selective activity at MC4R and MC1R subtypes. The compound acts centrally via hypothalamic melanocortin pathways, representing a mechanistically distinct class from PDE5 inhibitors. Bremelanotide demonstrates an IC50 of 2.9 nM at the MC4R receptor in binding assays, confirming potent and selective receptor engagement. The compound has achieved FDA approval (marketed as Vyleesi), making it one of the most thoroughly characterized melanocortin receptor ligands available for preclinical research.

Key Research Findings:

• In vitro receptor binding assays established an IC50 of 2.9 nM at MC4R, with measurable MC1R affinity and minimal activity at MC2R/MC3R/MC5R
• Preclinical models demonstrated central nervous system activity via hypothalamic melanocortin circuits, distinct from peripheral PDE5 inhibition mechanisms
• Rodent studies confirmed dose-dependent activation of MC4R-mediated signaling cascades in hypothalamic tissue
• Pharmacological profiling established Bremelanotide as a selective melanocortin agonist without significant off-target receptor binding

For laboratory and research use only.